Design Of ERM Based On Linux Operating System

With the rapid development of urban rail transit and train equipment becomes more and more complex,the difficulty of equipment troubleshooting is increasing gradually.As one of the train safety equipment,ERM(Event Recorder Module)records the real-time operating situation of the train equipment,and provides data support for fault analysis or operation maintenance.The data that ERM records have legal status.In view of the monopoly of foreign train equipment technology,the domestic urban rail train event recorder does not record data comprehensively,the memory security protection is insufficient and the data security coefficient is not high.So it is of great significance to research a configurable train event recorder with data encryption algorithm.The thesis analyzes the characteristics of TCN(Train Communication Network)and adopts a modular design based on kinds of actual train data sources.An overall design scheme of ERM based on Linux embedded operating system is proposed and completed including the design of hardware,operating system and application software.In the hardware part,it adopts a flexible configuration scheme that takes a master board and several expansion boards to composite in order to adapt different train models.And the subject completed the hardware circuit design of the control module,power supply module,digital acquisition module,analog acquisition module,MVB(Multifunction Vehicle Bus)data acquisition module and communication module with AM3358 as the core.In the software part,Linux embedded operating system is selected as the system platform by analyzing the characteristics of software system of ERM.The subject mainly completes the building of software development environment,the design and transplantation of embedded Linux operating system,the programming of functional module drivers such as MVB driver,and the compiling of main application program and sub-program acquisition of each module.Aiming at the problems of data security and data integrity,this thesis designs an ERM-ES algorithm specifically applied to ERM realizing the function of data encryption and dump.In the laboratory environment,a simulation test platform is built to verify the functions of ERM.The experimental results show that the event recorder can implement the function of data encryption and data integrity verification on the basis of data collection.Thus,the experimental results verify the feasibility of the scheme and satisfy the requirement the recorded data of the train event recorder have a legal basis that cannot be tampered with.So it is worthwhile to expand for application.